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  <div class="section" id="the-python-language-reference">
<span id="reference-index"></span><h1>The Python Language Reference<a class="headerlink" href="#the-python-language-reference" title="Permalink to this headline">¶</a></h1>
<p>This reference manual describes the syntax and &#8220;core semantics&#8221; of the
language. It is terse, but attempts to be exact and complete. The semantics of
non-essential built-in object types and of the built-in functions and modules
are described in <a class="reference internal" href="../library/index.html#library-index"><em>The Python Standard Library</em></a>. For an informal introduction to the
language, see <a class="reference internal" href="../tutorial/index.html#tutorial-index"><em>The Python Tutorial</em></a>. For C or C++ programmers, two additional
manuals exist: <a class="reference internal" href="../extending/index.html#extending-index"><em>Extending and Embedding the Python Interpreter</em></a> describes the high-level picture of how to
write a Python extension module, and the <a class="reference internal" href="../c-api/index.html#c-api-index"><em>Python/C API Reference Manual</em></a> describes the
interfaces available to C/C++ programmers in detail.</p>
<div class="toctree-wrapper compound">
<ul>
<li class="toctree-l1"><a class="reference internal" href="introduction.html">1. Introduction</a><ul>
<li class="toctree-l2"><a class="reference internal" href="introduction.html#alternate-implementations">1.1. Alternate Implementations</a></li>
<li class="toctree-l2"><a class="reference internal" href="introduction.html#notation">1.2. Notation</a></li>
</ul>
</li>
<li class="toctree-l1"><a class="reference internal" href="lexical_analysis.html">2. Lexical analysis</a><ul>
<li class="toctree-l2"><a class="reference internal" href="lexical_analysis.html#line-structure">2.1. Line structure</a></li>
<li class="toctree-l2"><a class="reference internal" href="lexical_analysis.html#other-tokens">2.2. Other tokens</a></li>
<li class="toctree-l2"><a class="reference internal" href="lexical_analysis.html#identifiers">2.3. Identifiers and keywords</a></li>
<li class="toctree-l2"><a class="reference internal" href="lexical_analysis.html#literals">2.4. Literals</a></li>
<li class="toctree-l2"><a class="reference internal" href="lexical_analysis.html#operators">2.5. Operators</a></li>
<li class="toctree-l2"><a class="reference internal" href="lexical_analysis.html#delimiters">2.6. Delimiters</a></li>
</ul>
</li>
<li class="toctree-l1"><a class="reference internal" href="datamodel.html">3. Data model</a><ul>
<li class="toctree-l2"><a class="reference internal" href="datamodel.html#objects-values-and-types">3.1. Objects, values and types</a></li>
<li class="toctree-l2"><a class="reference internal" href="datamodel.html#the-standard-type-hierarchy">3.2. The standard type hierarchy</a></li>
<li class="toctree-l2"><a class="reference internal" href="datamodel.html#new-style-and-classic-classes">3.3. New-style and classic classes</a></li>
<li class="toctree-l2"><a class="reference internal" href="datamodel.html#special-method-names">3.4. Special method names</a></li>
</ul>
</li>
<li class="toctree-l1"><a class="reference internal" href="executionmodel.html">4. Execution model</a><ul>
<li class="toctree-l2"><a class="reference internal" href="executionmodel.html#naming-and-binding">4.1. Naming and binding</a></li>
<li class="toctree-l2"><a class="reference internal" href="executionmodel.html#exceptions">4.2. Exceptions</a></li>
</ul>
</li>
<li class="toctree-l1"><a class="reference internal" href="expressions.html">5. Expressions</a><ul>
<li class="toctree-l2"><a class="reference internal" href="expressions.html#arithmetic-conversions">5.1. Arithmetic conversions</a></li>
<li class="toctree-l2"><a class="reference internal" href="expressions.html#atoms">5.2. Atoms</a></li>
<li class="toctree-l2"><a class="reference internal" href="expressions.html#primaries">5.3. Primaries</a></li>
<li class="toctree-l2"><a class="reference internal" href="expressions.html#the-power-operator">5.4. The power operator</a></li>
<li class="toctree-l2"><a class="reference internal" href="expressions.html#unary-arithmetic-and-bitwise-operations">5.5. Unary arithmetic and bitwise operations</a></li>
<li class="toctree-l2"><a class="reference internal" href="expressions.html#binary-arithmetic-operations">5.6. Binary arithmetic operations</a></li>
<li class="toctree-l2"><a class="reference internal" href="expressions.html#shifting-operations">5.7. Shifting operations</a></li>
<li class="toctree-l2"><a class="reference internal" href="expressions.html#binary-bitwise-operations">5.8. Binary bitwise operations</a></li>
<li class="toctree-l2"><a class="reference internal" href="expressions.html#not-in">5.9. Comparisons</a></li>
<li class="toctree-l2"><a class="reference internal" href="expressions.html#boolean-operations">5.10. Boolean operations</a></li>
<li class="toctree-l2"><a class="reference internal" href="expressions.html#conditional-expressions">5.11. Conditional Expressions</a></li>
<li class="toctree-l2"><a class="reference internal" href="expressions.html#lambda">5.12. Lambdas</a></li>
<li class="toctree-l2"><a class="reference internal" href="expressions.html#expression-lists">5.13. Expression lists</a></li>
<li class="toctree-l2"><a class="reference internal" href="expressions.html#evaluation-order">5.14. Evaluation order</a></li>
<li class="toctree-l2"><a class="reference internal" href="expressions.html#operator-precedence">5.15. Operator precedence</a></li>
</ul>
</li>
<li class="toctree-l1"><a class="reference internal" href="simple_stmts.html">6. Simple statements</a><ul>
<li class="toctree-l2"><a class="reference internal" href="simple_stmts.html#expression-statements">6.1. Expression statements</a></li>
<li class="toctree-l2"><a class="reference internal" href="simple_stmts.html#assignment-statements">6.2. Assignment statements</a></li>
<li class="toctree-l2"><a class="reference internal" href="simple_stmts.html#the-assert-statement">6.3. The <tt class="docutils literal"><span class="pre">assert</span></tt> statement</a></li>
<li class="toctree-l2"><a class="reference internal" href="simple_stmts.html#the-pass-statement">6.4. The <tt class="docutils literal"><span class="pre">pass</span></tt> statement</a></li>
<li class="toctree-l2"><a class="reference internal" href="simple_stmts.html#the-del-statement">6.5. The <tt class="docutils literal"><span class="pre">del</span></tt> statement</a></li>
<li class="toctree-l2"><a class="reference internal" href="simple_stmts.html#the-print-statement">6.6. The <tt class="docutils literal"><span class="pre">print</span></tt> statement</a></li>
<li class="toctree-l2"><a class="reference internal" href="simple_stmts.html#the-return-statement">6.7. The <tt class="docutils literal"><span class="pre">return</span></tt> statement</a></li>
<li class="toctree-l2"><a class="reference internal" href="simple_stmts.html#the-yield-statement">6.8. The <tt class="docutils literal"><span class="pre">yield</span></tt> statement</a></li>
<li class="toctree-l2"><a class="reference internal" href="simple_stmts.html#the-raise-statement">6.9. The <tt class="docutils literal"><span class="pre">raise</span></tt> statement</a></li>
<li class="toctree-l2"><a class="reference internal" href="simple_stmts.html#the-break-statement">6.10. The <tt class="docutils literal"><span class="pre">break</span></tt> statement</a></li>
<li class="toctree-l2"><a class="reference internal" href="simple_stmts.html#the-continue-statement">6.11. The <tt class="docutils literal"><span class="pre">continue</span></tt> statement</a></li>
<li class="toctree-l2"><a class="reference internal" href="simple_stmts.html#the-import-statement">6.12. The <tt class="docutils literal"><span class="pre">import</span></tt> statement</a></li>
<li class="toctree-l2"><a class="reference internal" href="simple_stmts.html#the-global-statement">6.13. The <tt class="docutils literal"><span class="pre">global</span></tt> statement</a></li>
<li class="toctree-l2"><a class="reference internal" href="simple_stmts.html#the-exec-statement">6.14. The <tt class="docutils literal"><span class="pre">exec</span></tt> statement</a></li>
</ul>
</li>
<li class="toctree-l1"><a class="reference internal" href="compound_stmts.html">7. Compound statements</a><ul>
<li class="toctree-l2"><a class="reference internal" href="compound_stmts.html#the-if-statement">7.1. The <tt class="docutils literal"><span class="pre">if</span></tt> statement</a></li>
<li class="toctree-l2"><a class="reference internal" href="compound_stmts.html#the-while-statement">7.2. The <tt class="docutils literal"><span class="pre">while</span></tt> statement</a></li>
<li class="toctree-l2"><a class="reference internal" href="compound_stmts.html#the-for-statement">7.3. The <tt class="docutils literal"><span class="pre">for</span></tt> statement</a></li>
<li class="toctree-l2"><a class="reference internal" href="compound_stmts.html#the-try-statement">7.4. The <tt class="docutils literal"><span class="pre">try</span></tt> statement</a></li>
<li class="toctree-l2"><a class="reference internal" href="compound_stmts.html#the-with-statement">7.5. The <tt class="docutils literal"><span class="pre">with</span></tt> statement</a></li>
<li class="toctree-l2"><a class="reference internal" href="compound_stmts.html#function-definitions">7.6. Function definitions</a></li>
<li class="toctree-l2"><a class="reference internal" href="compound_stmts.html#class-definitions">7.7. Class definitions</a></li>
</ul>
</li>
<li class="toctree-l1"><a class="reference internal" href="toplevel_components.html">8. Top-level components</a><ul>
<li class="toctree-l2"><a class="reference internal" href="toplevel_components.html#complete-python-programs">8.1. Complete Python programs</a></li>
<li class="toctree-l2"><a class="reference internal" href="toplevel_components.html#file-input">8.2. File input</a></li>
<li class="toctree-l2"><a class="reference internal" href="toplevel_components.html#interactive-input">8.3. Interactive input</a></li>
<li class="toctree-l2"><a class="reference internal" href="toplevel_components.html#expression-input">8.4. Expression input</a></li>
</ul>
</li>
<li class="toctree-l1"><a class="reference internal" href="grammar.html">9. Full Grammar specification</a></li>
</ul>
</div>
</div>


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